Child safety seats for use in automobiles have been designed to include a variety of features. Many of these features relate to either improved safety of the seat or increased convenience and ease of use of the child safety seat. Specifically, one area of focus within the relevant market is the ability to adjust the restraint system of the safety seat for a growing child. Still, despite the significant efforts made in advancing child safety seat technology, many such seats remain difficult to install and adjust, and offer little advancement in the area of improved safety.
Many child safety seats offer the ability to adjust the height of shoulder belts of the harness system as a child grows taller. The most common method of allowing for adjustment of the shoulder belts is to provide a plurality of vertically spaced pairs of slots in the seat back. When desired, the shoulder belts are drawn back through the slots to the back of the safety seat and then inserted through a higher pair of slots. While this method of adjusting the shoulder belts is ultimately effective, it is also time consuming and awkward because it requires removing the safety seat from a vehicle, often meaning removing a child from the safety seat, adjusting the shoulder belts, and then reinstalling the safety seat in the vehicle. Other mechanisms have been developed in an attempt to make adjustment of the shoulder restraints simpler and less time consuming. However, these attempts still require access to the rear of the safety seat in order to permit adjustment of the shoulder restraint belts, thus still requiring removal of the seat from the vehicle.
Another design element of child safety seats that has been the focus of much attempted innovation is the mechanism by which the seat is secured within a vehicle. The conventional safety seat utilizes the vehicle's safety belt to secure it within the vehicle, often requiring the safety belt to be threaded through an opening in the seat. More recently, due in part to government regulations, the LATCH system as it is known in the United States (also referred to as ISOFIX in Europe, LUAS or CANFIX in Canada, and UCSSS) has become more prominent. These systems include two lower anchor attachments and may include a top tether attachment, and are adapted to be attached to hooks provided in newer vehicles. The lower anchor attachments of the LATCH system may be provided in the form of a flexible belt with hook ends, or rigid attachments extending from the safety seat. In the case of a seat having rigid attachments, while installation of the seat is made more convenient, removal of the seat can be somewhat difficult due to the hard-to-reach location of the release mechanism for the rigid latch members.
One area that has received surprisingly little research and development within the safety seat industry is force dampening mechanisms, or energy absorbing systems, incorporated into the seats to reduce the forces felt by a child during an accident. Many advances have been made in the field of air-bags and other similar devices that reduce the forces felt by an adult in a car accident, but similar developments have not been seen in the field of child safety seats. One known mechanism for absorbing forces acting on a child safety seat during a crash, as disclosed in U.S. Pat. No. 5,664,830, involves providing a base and a seat body, the base and seat body being slidingly connected by a track system. The seat body is anchored and secured in place relative to the base by a shear pin, and a honey-comb core cylinder is positioned between the seat body and the base in the path of movement. When a load threshold has been surpassed during a collision, the shear pin is overcome and the seat body pivots on the track system relative to the base, thereby crushing the cylinder to absorb the forces of the crash. This system, however, does not take into account the varying size and weight of children occupying a child safety seat. A single resistance is provided by the energy absorbing cylinder, which often results in ineffective force dampening due to either insufficient energy absorption for a larger child or too much resistance for a smaller child.
Thus, the need exists for a child safety seat that alleviates one or more of these deficiencies of the prior art.